Loudspeakers and related components and methods

ABSTRACT

A loudspeaker includes an acoustic enclosure, and an electro-acoustic transducer that is supported by the acoustic enclosure. A grille covers the electro-acoustic transducer, and a weather-resistant member is disposed between the acoustic enclosure and the grille. A spring member is disposed between the weather-resistant member and the acoustic enclosure. The spring member is configured to apply a force to the weather-resistant layer thereby to hold the weather-resistant member against the grille.

BACKGROUND

This disclosure relates to a loudspeaker, and, more particularly, to aloudspeaker having a weather-resistant grille assembly.

SUMMARY

All examples and features mentioned below can be combined in anytechnically possible way.

In one aspect, a loudspeaker includes an acoustic enclosure, and anelectro-acoustic transducer that is supported by the acoustic enclosure.A grille covers the electro-acoustic transducer, and a weather-resistantmember is disposed between the acoustic enclosure and the grille. Aspring member is disposed between the weather-resistant member and theacoustic enclosure. The spring member is configured to apply a force tothe weather-resistant layer thereby to hold the weather-resistant memberagainst the grille.

Implementations may include one of the following features, or anycombination thereof.

In some implementations, the weather-resistant member includes a scrimlayer. The scrim layer may be formed of an acoustically transparentsheet form foam material.

In certain implementations, the spring member includes a substantiallyarcuate main body that extends between a par of opposing sidewalls.

In some examples, the substantially arcuate main body is biasedoutwardly, away from the acoustic enclosure, such that a concave side ofthe main body faces toward the housing.

In certain examples, the arcuate main body includes a plurality ofcross-members.

In some cases, the cross-members extend diagonally relative to thesidewalls.

In certain cases, the cross-members intersect with each other at nodes.

In some implementations, the cross-members are arranged to form a notchto accommodate the geometry of the electro-acoustic transducer.

In certain implementations, the weather-resistant layer includes ascreen layer disposed between the spring member and the scrim layer. Thespring member may be configured to apply a force to the screen layer tohold a front surface of the screen layer against a rear surface of thescrim layer and to hold a front surface of the scrim layer against arear surface of the grille.

In some examples, the weather-resistant member consists of a screenlayer.

In certain examples, the screen layer includes an acousticallytransparent sheet form material formed of a woven fabric. The wovenfabric may be formed of metal filaments. In some cases, the screen layermay be formed of cloth.

Another aspect provides a grille assembly for a loudspeaker. The grilleassembly includes a grille, a spring member, and a weather-resistantmember disposed between the spring member and the grille. The springmember is configured to apply a force between an acoustic enclosure of aloudspeaker and the weather-resistant layer to hold a front surface ofthe weather-resistant member substantially flush against a rear surfaceof the grille.

Implementations may include one of the above and/or below features, orany combination thereof.

In some implementations, the weather-resistant member includes a scrimlayer.

In certain implementations, the scrim layer is formed of an acousticallytransparent sheet form foam material.

In some examples, the spring member includes a substantially arcuatemain body that extends between a par of opposing sidewalls.

In certain examples, the sidewalls terminate at a pair of feet, whichare arranged to rest against a surface of an acoustic enclosure of aloudspeaker.

In some cases, the substantially arcuate main body is biased outwardly,away from the acoustic enclosure, such that a concave side of the mainbody faces toward the housing.

In certain cases, the arcuate main body includes a plurality ofcross-members.

In some implementations, the cross-members extend diagonally relative tothe sidewalls.

In certain implementations, the cross-members intersect with each otherat nodes.

In some examples, the cross-members are arranged to form a notch toaccommodate the geometry of an electro-acoustic transducer of theloudspeaker.

In certain examples, the weather-resistant layer includes a screen layerdisposed between the spring member and the scrim layer. The springmember may be configured to apply a force to the screen layer to hold afront surface of the screen layer against a rear surface of the scrimlayer and to hold a front surface of the scrim layer against a rearsurface of the grille.

In some cases, the weather-resistant member consists of a screen layer.

In certain cases, the screen layer comprises an acoustically transparentsheet form material formed of a woven fabric of metal filaments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an exploded perspective view of a first implementation of aloudspeaker.

FIG. 1B is an exploded perspective view of a grille assembly from theloudspeaker of FIG. 1A.

FIG. 2A is an exploded perspective view of a second implementation of aloudspeaker.

FIG. 2B is an exploded perspective view of a grille assembly from theloudspeaker of FIG. 2A.

DETAILED DESCRIPTION

This disclosure is based, at least in part, on the realization that itcan be beneficial to provide structural support to a scrim backing layerin a weather-resistant loudspeaker.

With reference to FIG. 1A, a loudspeaker 100 includes an acousticassembly 102, a grille assembly 104, and an input/output (I/O) assembly106. Notably the grille assembly 104 is configured to beweather-resistant, thereby to protect components of the acousticassembly 102 from moisture to enable outdoor use of the loudspeaker 100.

Acoustic Assembly

The acoustic assembly 102 includes an acoustic enclosure 108 and aplurality of electro-acoustic transducers 110, 112, which are supportedby the acoustic enclosure 108. The acoustic enclosure 108 includes acabinet 114 and a baffle 116. The cabinet 114 and the baffle 116 may beformed of a rigid material such as metal, hard plastic, wood (e.g.,plywood), or fiber board (e.g., medium-density fiberboard (MDF). Thebaffle 116 includes a plurality of openings 118, 120 for receiving theelectro-acoustic transducers 110, 112. The cabinet 114 and the baffle116 together define an acoustic cavity 122.

In the illustrated example, the electro-acoustic transducers 110, 112include a high-frequency (HF) transducer 110 and a low-frequency (LF)transducer 112. The HF transducer 110 includes a compression driver 124that is coupled a throat of a horn 126. The compression driver 124 ispassed through a first opening 118 in the baffle 116 and is receivedwithin the acoustic cavity 122. A mouth of the horn 126 is secured tothe baffle 116 via a frame 128 that surrounds the mouth. A gasket 130 isdisposed between the frame 128 and the baffle 116 to inhibit buzz andprovide an acoustic seal between the frame 128 and the acoustic cavity122. The frame 128 is secured to the baffle 116 with fasteners 132.

An electro-magnetic motor 134 of the LF transducer 112 is passed througha second opening 120 in the baffle 116 and is received within theacoustic cavity 122. The LF transducer 112 is secured to the baffle 116via a frame 136. A gasket 138 is disposed between the frame 136 and thebaffle 116 to inhibit buzz and provide an acoustic seal between theframe 136 and the acoustic cavity 122. The frame 136 is secured to thebaffle 116 with fasteners 140. The LF transducer 112 is arranged suchthat a rear radiating surface of the LF transducer 112 radiates acousticenergy into the acoustic cavity 122.

Grille Assembly

Referring to FIG. 1B, the grille assembly 104 includes a grille 142, aweather-resistant member 144, and a spring member 146. The grille 142has a substantially arcuate main body 148 that extends between a pair ofopposing sidewalls 150. The main body 148 includes a plurality ofapertures 152 that allow acoustic energy, radiated by theelectro-acoustic transducers 110, 112 to pass through the grille 142.The sidewalls 150 include a plurality of mounting holes 154 forreceiving fasteners 156 (FIG. 1A) for securing the grille 154 to theacoustic enclosure 108 (FIG. 1A). The grille 142 can be formed of arigid material such as a metal (e.g., stainless steel) or hard plastic.

The weather-resistant member 144 is a sheet form material that overliesthe apertures 152 along a rear surface of the grille 142. Theweather-resistant member 144 is acoustically transparent and isconfigured to inhibit water and dust from entering. In that regard, theapertures 152 may allow water to pass through the grille 142. This ismore likely when the loudspeaker 100 is mounted outdoors and is subjectto the elements include, for example, driving rain. Theweather-resistant member 144 is configured to inhibit (e.g., prevent)water that passes through the grille 142 from reaching theelectro-acoustic transducers 110, 112. In some cases, theweather-resistant member 144 is configured to enable the loudspeaker 100to pass IPX testing, which tests against driven water and dust). In someimplementations, the loudspeaker is weather-resistant beyond a minimumIPX rating of IPX IP55.

In the illustrated example, the weather-resistant member 144 includes ascrim layer 158 and a screen layer 160. The scrim layer 158 is a firstbarrier against water and dust infiltration. The scrim layer 158 may beformed from a sheet form foam material, such as a polyethylene foam. Onesuitable material for the scrim layer 158 is 60 PPI fireproofpolyethylene foam with a thickness of 2 mm to 10 mm, e.g., 4 mmthickness. The screen layer 160 is second barrier against water and dustinfiltration. In some cases, the screen layer 160 may help to ensurethat forces applied to rear surface of the scrim layer 158 (as describedbelow) are more evenly distributed. The screen layer 160 is anotheracoustically transparent sheet form material and may be formed of awoven fabric of metal filaments (e.g., 316H stainless steel woven wiremesh).

A front surface of the scrim layer 158 rests against a rear surface ofthe grille 142, and a front surface of the screen layer 160 restsagainst a rear surface of the scrim layer 158. Prolonged exposure to theelements, such as wind and rain, might cause the weather-resistantmember 144 to sag. The sagging of the weather-resistant member 144 mightresult in flapping, i.e., movement of the member 144 during use, whichmight result undesirable acoustic effects. For example, theweather-resistant member 144 could be forced against theelectro-acoustic transducers and thereby affect acoustics. Sagging ofthe weather-resistant member 144 might also allow water to pool betweenthe grille 142 and the weather-resistant member 144, which mightultimately contribute to failure of the weather-resistant member 144. Insome instances, the weather-resistant member 144 also serves as acosmetic backing to the grille 142, and sagging might degrade thecosmetic appearance of the loudspeaker 100.

In some cases, adhesives may be used to secure the water-resistantmember 144 to the grille 142. For example, the scrim layer 158 may besecured to the grille 142 with an adhesive. Alternatively oradditionally, the screen layer 160 may be secured to the scrim layer 158with an adhesive. However, with prolonged exposure to the elements,adhesives can fail. As a result, adhesives alone might only help todelay, but not prevent, sagging of the water-resistant member 144.Adhesives might also occlude pores and openings in the water-resistantmember 144, which can adversely affect the acoustic transparency of thewater-resistant member 144.

The spring member 146 is configured to provide prolonged protectionagainst sag. The spring member 146 includes a substantially arcuate mainbody 162 that extends between a pair of opposing sidewalls 164, whichterminate at a pair of feet 166. The curvature of the main body 162 ofthe spring member 146 conforms generally to that of the main body 148(FIG. 1) of the grille 142. The arcuate main body 162 includes aplurality of cross-members 168, which extend diagonally relative to thesidewalls 164. The cross-members 168 intersect with each other at nodes170. Open regions 172 between the cross-members 168 allow for acousticenergy radiate by the electro-acoustic transducers to pass therethrough.

Preferably, the spring member 146 is designed such that thecross-members 168 and nodes 170 are spaced away from the motion axes ofthe electro-acoustic transducers 110, 112 (FIG. 1A), e.g., such thatrespective ones of the open regions 172 are centered along the motionaxes of the electro-acoustic transducers 110, 112.

The cross-members 168 have a width (w) of 5 mm or less (e.g., 4 mm-5mm). Cross-members with a width greater than 5 mm can undesirablyinterfere with audible frequencies produced by the electro-acoustictransducers 110, 112. The spring member 146 can be formed of metal, suchas stainless steel. In one example, the spring member 146 is formed froma sheet of stainless steel that is punched to form the cross-members,and bend to shape to impart a curvature to the main body 162 and to formthe sidewalls 164 and feet 166.

The main body 162 extends along a rear surface of the water-resistantmember 144. the substantially arcuate main body 162 is biased outwardly,away from the acoustic enclosure 108, such that a concave side the mainbody 162 faces toward the acoustic enclosure 108 and an opposite, convexside faces toward the concave inner surface of the grille 142.

The feet 166 sit on the acoustic enclosure 108 (FIG. 1A) and allow forthe main body 162 of the spring member 146 to apply a force to the rearsurface of the water-resistant member 144. A gasket 174 (e.g., anethylene-vinyl acetate (EVA) gasket) may be disposed between the feet166 and the acoustic enclosure 108 to help inhibit buzz.

The grille 142 is coupled to the acoustic enclosure 108 (FIG. 1A) viafasteners 156 (FIG. 1A), thereby securing the spring member 146 betweenthe grille 142 and the acoustic enclosure 108 and sandwiching thewater-resistant member 144 between the grille 142 and the spring member146. When assembled, the spring member 146 applies a compressive forcealong the rear surface of the water-resistant member 144, thereby tohold a front surface of the water-resistant member 144 in close contactwith the rear surface of the grille 142. In that regard, followingassembly, the spring member 146 compresses the water-resistant member144 between 0.5 mm and 2 mm (e.g., between 10% and 25% of itsuncompressed thickness).

As a result, the spring member 146 helps to ensure that thewater-resistant member 144 remains in close contact with the grille 142even after prolonged exposure to the elements, thereby reducing thelikelihood of sagging and the resulting flapping, potential loss ofwater-resistance, and deteriorated cosmetic appearance. The inclusion ofthe spring member 146 can also alleviate the need for adhesives on thesurfaces of the water-resistant member 144 which can occlude openingsand adversely affect the acoustic transparency of the water-resistantmember 144.

A gasket 176 (e.g., an ethylene-vinyl acetate (EVA) gasket) may bedisposed between the grille 142 and the acoustic enclosure 108 (FIG. 1A)to inhibit buzz. In some implementations, the gasket 174 (between thespring member 146 and the acoustic enclosure 108) and the gasket 176(between the grille 142 and the acoustic enclosure 108) may be formedfrom one piece of material. For example, a single strip of gasketmaterial may be folded along its length to provide a first gasketportion to sit between the spring member 146 and the acoustic enclosure108, and a second gasket portion to sit between the grille 142 and theacoustic enclosure 108.

I/O Assembly

Referring again to FIG. 1, the I/O assembly 106 is mounted to a rearsurface of the acoustic enclosure 108 for coupling electrical wires (notshown) to power the electro-acoustic transducers 110, 112. The I/Oassembly 106 includes an I/O panel 178 and an I/O cover 180. The I/Opanel 178 includes a mounting plate 182 that supports a terminal strip184, a transformer 186, and a selector switch 188. The terminal strip184 allows electrical wires to be connected to the loudspeaker 100 topower the electro-acoustic transducers 110, 112 (i.e., via an opening,not shown, in a rear surface the acoustic enclosure 108). The selectorswitch 188 can be a rotary switch from selecting among the multiple tapsof the transformer 186.

The mounting plate 182 is secured to the acoustic enclosure 108 viafasteners 190. A gasket 192 (e.g., an ethylene-vinyl acetate (EVA)gasket) is disposed between the mounting plate 182 and the acousticenclosure 108 to provide a water-resistant seal. The gasket 192 can alsohelp to provide an acoustic seal (e.g., to inhibit leakage of acousticenergy from the acoustic enclosure 108), and inhibit buzz (e.g., betweenthe acoustic enclosure 108 and the mounting plate 182).

The I/O cover 180 provides water-resistant protection for the terminalstrip 184 and may formed as a molded plastic part. The I/O cover 180 issecured to the mounting plate 182 with fasteners 194. A gasket 196(e.g., an ethylene-vinyl acetate (EVA) gasket) provides awater-resistant seal between the I/O cover 180 and the mounting plate182 and can also help to inhibit buzz therebetween.

Other Implementations

While one or more implementations of a loudspeaker have been describedabove, other implementations are possible. For example, FIG. 2Aillustrates another loudspeaker 200. The loudspeaker 200 includes anacoustic assembly 202, a grille assembly 204, and an I/O assembly 206.The grille assembly 204 may have a similar construction to the onedescribed above with respect to FIG. 1B. As shown in FIG. 2B, the grilleassembly 204 may include a grille 208, a water-resistant member 210including a scrim layer 212 and a screen layer 214, and a spring member216. However, in the implementation illustrated in FIGS. 2A & 2B,cross-members 218 of the spring member 216 define a notch 220. The notch220 is configured to accommodate the geometry of an electro-acoustictransducer 222 (FIG. 2A); i.e., to prevent the spring member 216 frominterfering with the electro-acoustic transducer 222.

In some implementations, the weather-resistant member may consist of ascrim layer without a screen backing layer. Alternatively, theweather-resistant member may consist of a screen layer without a scrimlayer. In some cases, the loudspeaker may include a cosmetic material asan alternative to or in addition to the weather-resistant member.

While an implementation has been described in which the spring member isformed of stamped and formed sheet metal, an alternative spring membercould be formed of wire mesh (e.g., “chicken wire”) that is bend toshape.

In some implementations, the cross-members could extend betweensidewalls and substantially perpendicular thereto.

While an implementation has been described in which the spring memberhas substantially arcuate main body that is biased outwardly, away fromthe acoustic enclosure, in other implementations the main body of thespring member can be flat or inwardly curved, e.g., to work which flator inwardly curved grille.

A number of implementations have been described. Nevertheless, it willbe understood that additional modifications may be made withoutdeparting from the scope of the inventive concepts described herein,and, accordingly, other implementations are within the scope of thefollowing claims.

What is claimed is:
 1. A loudspeaker comprising: an acoustic enclosure;an electro-acoustic transducer supported by the acoustic enclosure; agrille covering the electro-acoustic transducer; a weather-resistantmember disposed between the acoustic enclosure and the grille; and aspring member disposed between the weather-resistant member and theacoustic enclosure, wherein the spring member is configured to apply aforce to the weather-resistant member thereby to hold theweather-resistant member against the grille, wherein the spring membercomprises an arcuate main body that extends between a pair of opposingsidewalls.
 2. The loudspeaker of claim 1, wherein the weather-resistantmember comprises a scrim layer.
 3. The loudspeaker of claim 2, whereinthe scrim layer is formed of an acoustically transparent sheet form foammaterial.
 4. The loudspeaker of claim 1, wherein the arcuate main bodyis biased outwardly, away from the acoustic enclosure, such that aconcave side of the main body faces toward the acoustic enclosure. 5.The loudspeaker of claim 4, wherein the arcuate main body comprises aplurality of cross-members.
 6. The loudspeaker of claim 5, wherein thecross-members extend diagonally relative to the sidewalls.
 7. Theloudspeaker of claim 5, wherein the cross-members intersect with eachother at nodes.
 8. The loudspeaker of claim 5, wherein the cross-membersare arranged to form a notch to accommodate the geometry of theelectro-acoustic transducer.
 9. The loudspeaker of claim 2, wherein theweather-resistant member further comprises a screen layer disposedbetween the spring member and the scrim layer, wherein the spring memberis configured to apply a force to the screen layer to hold a frontsurface of the screen layer against a rear surface of the scrim layerand to hold a front surface of the scrim layer against a rear surface ofthe grille.
 10. The loudspeaker of claim 9, wherein the screen layercomprises an acoustically transparent sheet form material formed of awoven fabric of metal filaments.
 11. The loudspeaker of claim 1, whereinthe weather-resistant member comprises a screen layer.
 12. Theloudspeaker of claim 11, wherein the screen layer comprises anacoustically transparent sheet form material formed of a woven fabric ofmetal filaments.
 13. A grille assembly for a loudspeaker, the grilleassembly comprising: a grille; a spring member; and a weather-resistantmember disposed between the spring member and the grille, wherein thespring member is configured to apply a force between an acousticenclosure of a loudspeaker and the weather-resistant member to hold afront surface of the weather-resistant member substantially flushagainst a rear surface of the grille, wherein the spring membercomprises an arcuate main body that extends between a pair of opposingsidewalls.
 14. The grille assembly of claim 13, wherein theweather-resistant member comprises a scrim layer.
 15. The grilleassembly of claim 14, wherein the scrim layer is formed of anacoustically transparent sheet form foam material.
 16. The grilleassembly of claim 13, wherein the sidewalls terminate at a pair of feet,which are arranged to rest against a surface of the acoustic enclosureof the loudspeaker.
 17. The loudspeaker of claim 13, wherein the arcuatemain body is biased outwardly, away from the acoustic enclosure, suchthat a concave side of the main body faces toward the acousticenclosure.
 18. The grille assembly of claim 13, wherein the arcuate mainbody comprises a plurality of cross-members.
 19. The grille assembly ofclaim 18, wherein the cross-members extend diagonally relative to thesidewalls.
 20. The grille assembly of claim 18, wherein thecross-members intersect with each other at nodes.
 21. The grilleassembly of claim 18, wherein the cross-members are arranged to form anotch to accommodate the geometry of an electro-acoustic transducer ofthe loudspeaker.
 22. The grille assembly of claim 14, wherein theweather-resistant member further comprises a screen layer disposedbetween the spring member and the scrim layer, wherein the spring memberis configured to apply a force to the screen layer to hold a frontsurface of the screen layer against a rear surface of the scrim layerand to hold a front surface of the scrim layer against a rear surface ofthe grille.
 23. The grille assembly of claim 22, wherein the screenlayer comprises an acoustically transparent sheet form material formedof a woven fabric of metal filaments.
 24. The grille assembly of claim13, wherein the weather-resistant member comprises a screen layer. 25.The grille assembly of claim 24, wherein the screen layer comprises anacoustically transparent sheet form material formed of a woven fabric ofmetal filaments.